This invention relates generally to adjustable side view mirrors for vehicles and, more particularly, provides a side view mirror adjusting system having means for electromagnetically locking the mirror glass so that the mirror glass is maintained at the adjusted condition not withstanding vehicular vibrations and/or ambient conditions.
Conventionally, side view mirror assemblies for vehicles include a housing, a mirror frame mounting structure secured within said housing, a mirror glass and a mirror glass adjusting mechanism secured to said mirror frame mounting structure and the mirror glass for selectively adjusting the orientation of the mirror glass and includes a pair of supporting members nested one within the other, the outer one of said supporting members being fixedly secured to the mounting frame and the inner supporting member being frictionally coupled to said outer supporting member and resiliently biased clamping means arranged to effect the frictional coupling and mirror means, including a mirror glass secured to said inner supporting member, said clamping means being capable of exerting sufficient force to maintain the orientation of said mirror glass against unintentional change from a set condition yet capable of being relaxed selectively to permit adjustment or resetting of such orientation.
One type of mounting arrangement comprises a pair of nested shells, the outer shell being fixed and secured to the frame or the like within a housing capable of being mounted to the vehicle body. The mirror glass is seated within a mirror bed seated within the inner shell so that the mirror has its reflective surface facing outwardly. Spring biased clamp means are provided to maintain the shells in fixed assembly yet are sufficiently resilient to permit movement of the inner shell relative to the outer shell and hence permit adjustment of the orientation of the mirror glass.
Characteristically, the clamp means may loosen with resultant displacement of the mirror glass from its desired or adjusted orientation. In normal use, vibrations from engine operation, wind, road surface conditions, etc. may fully or partially overcome the spring bias sufficiently to permit vibration of the inner shell and hence complementary vibration of the mirror bed with the mirror glass seated therein, resulting in blurring or like distortion of the mirror image, misorientation of the mirror bed, or involuntary adjustments of the mirror bed from a set orientation. Attempts to overcome these effects by increasing the friction between the sliding surfaces of the shells and minimizing the backlash between the mechanical elements of the assembly may reduce the effect of the vibratory motion but have the undesired result of increasing the torque load required to be overcome in making the desired positional adjustments. In instances where remotely directed manipulation of the mirror bed is provided, as by electric motors arranged to cause positional adjustments, the increased torque load results in material reduction in the durability thereof. Efforts to reduce these forces, while maintaining sufficient force to hold the mirror bed and mirror in an adjusted condition after adjustment has been made, have been less than satisfactory.